NFSv4: Don't exit the state manager without clearing NFS4CLNT_MANAGER_RUNNING

If we exit the NFSv4 state manager due to a umount, then we can end up
leaving the NFS4CLNT_MANAGER_RUNNING flag set. If another mount causes
the nfs4_client to be rereferenced before it is destroyed, then we end
up never being able to recover state.

Fixes: 47c2199b6e ("NFSv4.1: Ensure state manager thread dies on last ...")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: stable@vger.kernel.org # v4.15+
This commit is contained in:
Trond Myklebust 2018-11-05 11:10:50 -05:00
parent ccda4af0f4
commit 21a446cf18

View file

@ -2601,11 +2601,12 @@ static void nfs4_state_manager(struct nfs_client *clp)
nfs4_clear_state_manager_bit(clp);
/* Did we race with an attempt to give us more work? */
if (clp->cl_state == 0)
break;
return;
if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
break;
return;
} while (refcount_read(&clp->cl_count) > 1);
return;
goto out_drain;
out_error:
if (strlen(section))
section_sep = ": ";
@ -2613,6 +2614,7 @@ static void nfs4_state_manager(struct nfs_client *clp)
" with error %d\n", section_sep, section,
clp->cl_hostname, -status);
ssleep(1);
out_drain:
nfs4_end_drain_session(clp);
nfs4_clear_state_manager_bit(clp);
}